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- Li Yin, Jumei Zhang, XiuLi Lin, “Complete monotonicity related to the k-polygamma functions with applications”, Adv Differ Equ, 2019, № 1, 2019, 364
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- Feng Qi, Ravi P. Agarwal, “On complete monotonicity for several classes of functions related to ratios of gamma functions”, J Inequal Appl, 2019, № 1, 2019, 36
- Feng Qi, Bai-Ni Guo, “Complete monotonicity of divided differences of the di- and tri-gamma functions with applications”, Georgian Mathematical Journal, 23, № 2, 2016, 279
- Omelsaad Ahfaf, Ahmed Talat, Mansour Mahmoud, “Bounds and Completely Monotonicity of Some Functions Involving the Functions ψ′(l) and ψ″(l)”, Symmetry, 14, № 7, 2022, 1420
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